ملخص البحث :

ABSTRACT A laboratory study was conducted to test a four-stroke diesel engine’s performance when its SAE 50 engine oil was contaminated with water in three volumetric ratios, 0%, 0.2%, and 0.5%, and to determine which of the three ratios of water contamination most affects engine performance. The research performed a one-way ANOVA test with a probability level of 5% to compare the differences in average engine performance produced by the three contamination levels. Engine performance was gauged according to the following characteristics: friction power, fuel consumption, indicated power, and mechanical efficiency. The results showed significant differences at the 5% probability level resulting from increasing water contamination levels. The 0.5% contamination level produced the highest friction power (10.54625 kW), the highest fuel consumption (2.1659 kg/hr), the highest indicated power (16.17 kW), and the lowest mechanical efficiency (34.78595%). The results obtained show that the diesel engine's performance was affected when its engine oil was contaminated with water. According to the engine performance indicators that were studied, the engine performed well with low levels of water contamination (0%) and performed poorly with high levels of water contamination (0.5%). Thus, further research should be conducted to examine other contaminants that engine oil may be exposed to and determine their effects on diesel engines' performance.